Item #PG-057: This dropout has an integrated ISO disc mount located above the seatstay. It is machined from 6/4 titanium plate. The chainstay and seatstay tabs have a 58 degree included angle. The tabs are 5 mm thick, the dropout face and caliper mounting holes are 6.5 mm (+/- .5 mm) thick. It is chamfered 45 degrees x 1 mm around the outside profile and windows. The center of the axle to the center of the derailleur bolt is 1.180".